The present application relates for special techniques for cooling a special kind of bulb.
Special metal halide bulbs have special cooling requirements. The bulbs, such as Philips metal halide projection lamps, often have a central portion which emits light, and two “pinch” portions around the central portion.
A diagram of an exemplary one of these bulbs is shown in FIG. 1. The bulb has a central light emitting portion 100, and the two surrounding “pinch” portions 102, 104.
In some bulbs, it is desirable to keep the pinch portions 102, 104 cooler than the center portion. This is easy to do in a laboratory condition, but more difficult to do in practice.